Major Uses

Oxymorphone is an opiate agonist that is primarily used for dogs and cats as an injectable sedative/restraining agent, analgesic, and pre-anesthetic. It is occasionally used as an analgesic and anesthesia induction agent in horses. Oxymorphone can also be used in swine and rodents as an adjunctive analgesic.

Common Precautions

Severely debilitated or geriatric patients, as well as those with hypothyroidism, renal insufficiency, or adrenocortical insufficiency, should exercise caution when using oxymorphone. Oxymorphone should be used cautiously in animals with head injuries, increased intracranial pressure, or acute abdominal conditions.

Negative side effects associated with oxymorphone may include respiratory depression, bradycardia, panting, ataxia, hyperesthesia, and behavioral changes such as aggression and hyperexcitability. Decreased GI motility and CNS excitement may also occur while using this drug.

Oxymorphone should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if an overdose is suspected, the symptoms of which can be profound respiratory and/or CNS depression. Other symptoms of an overdose can include cardiovascular collapse, hypothermia, and skeletal muscle hypotonia.


Oxymorphone should be kept at room temperature and stored in a tight, light resistant, childproof container. It should be carefully protected from conditions that can cause freezing. The suppository form should be kept at a temperature between 35.6-59 degrees Fahrenheit.


A typical dose of oxymorphone in dogs ranges from .05-.4 mg/kg every 2-4 hours. For cats, a typical dose ranges from .02-.1 mg/kg every 2-6 hours. For horses, a normal dose is between .01-.03 mg/kg. Should a dose be forgotten, it should be administered as soon as possible unless it is almost time for the next scheduled dose. In this case, the missed dose should be skipped and the regular administration schedule should continue. Under no circumstances should two doses be administered at the same time.

Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.